ESE's works engine tuner

[HPbyGD]

Hi Guys
It was one of those projects where the guy came to me wanting to put a big bore job on his stock barrels. My thinking was that a lot of the big bore kits I have seen end up not making much of an improvement in the peak horsepower without LOTS of work. I started looking around for some cylinders to use that were already a bigger bore. That is when I found the DT 200 cylinders and after looking at one I thought that I could get two of them on the TZR 250 lower end. I would have liked to use WR 200 cylinders with the triple exhaust ports but they are a lot harder to find. The crank was stroked to 56 mm and 110 mm were installed. I did some dyno testing with a DT 200 lower end and was able to get 40 horsepower and a nice spread of power with the power valve. I know that the stroke on the DT was 1 mm longer but I thought it would give me at least a good indication of what the twin would be like. It wasn't to far off even though the guy didn't want to have me build a set of pipes like the one I used on the dyno and he decided to use the Jolly Motos that he all ready had. I didn't do much porting on the cylinder just a good clean up. The reed valves are for a Blaster and the carbs are 34 mm flat sides. I made a head for the DT that uses replaceable combustion chamber inserts. When I built the twin I made a head for it also. Makes it easy to try different combustion chambers or repair it if there is something damaged. I order to get the cylinders to fit on the lower end I had to cut the sides of the cylinder and then weld up the holes that appeared. Linking the power valves together took me a while to figure out. What I ended up doing was making a piece that fit into each end of the power valves and making a stud that went all the way through both power valves to hold every thing together. I made the stud out of drill rod and so far it has held up fine. That is most of the info and if you have any questions let me know and I will try and answer them. One other thing that I forgot to mentioned is that I have actually built two motor that were kind of similar. The other one the guy wanted to use big bore Athena TZR 125 cylinders. The guy went through some teething problems with the plating on the Athena cylinders. I don't think that the guy with the Athena cylinders ever pu tit on a dyno that I know of. Both of the motors used a Zeel ignitions.

Gary

So Gary can you give us some details regarding the engine as the post i quoted was rather thin.
like the stroke for instance.

[husaberg]

Hi Guys
It was one of those projects where the guy came to me wanting to put a big bore job on his stock barrels. My thinking was that a lot of the big bore kits I have seen end up not making much of an improvement in the peak horsepower without LOTS of work. I started looking around for some cylinders to use that were already a bigger bore. That is when I found the DT 200 cylinders and after looking at one I thought that I could get two of them on the TZR 250 lower end. I would have liked to use WR 200 cylinders with the triple exhaust ports but they are a lot harder to find. The crank was stroked to 56 mm and 110 mm were installed. I did some dyno testing with a DT 200 lower end and was able to get 40 horsepower and a nice spread of power with the power valve. I know that the stroke on the DT was 1 mm longer but I thought it would give me at least a good indication of what the twin would be like. It wasn't to far off even though the guy didn't want to have me build a set of pipes like the one I used on the dyno and he decided to use the Jolly Motos that he all ready had. I didn't do much porting on the cylinder just a good clean up. The reed valves are for a Blaster and the carbs are 34 mm flat sides. I made a head for the DT that uses replaceable combustion chamber inserts. When I built the twin I made a head for it also. Makes it easy to try different combustion chambers or repair it if there is something damaged. I order to get the cylinders to fit on the lower end I had to cut the sides of the cylinder and then weld up the holes that appeared. Linking the power valves together took me a while to figure out. What I ended up doing was making a piece that fit into each end of the power valves and making a stud that went all the way through both power valves to hold every thing together. I made the stud out of drill rod and so far it has held up fine. That is most of the info and if you have any questions let me know and I will try and answer them. One other thing that I forgot to mentioned is that I have actually built two motor that were kind of similar. The other one the guy wanted to use big bore Athena TZR 125 cylinders. The guy went through some teething problems with the plating on the Athena cylinders. I don't think that the guy with the Athena cylinders ever pu tit on a dyno that I know of. Both of the motors used a Zeel ignitions.

Gary

Thanks for that Gary.
So you would consider 56mm the limit for the stock TZR250 crank.
I also noticed there was some welding on the crankcases was this just to blend on the transfers or is the stud spacing different between the DT/WR200 and the TZR250.
Also if you know are the cranks similar to the RZ design or totally different.
Sorry for the thousand questions as i am not that familiar with the Yamaha's.
Actually i can't recall seeing a DT200 can remember the WR200 being around but they weren't that common either that i recall.

PS, that port layout is from a 6.6cc RC pylon racing engine, or at least the picture of the cylinder.

yes it was whoops

Jan stated that they had flow bench tested the RSW setup, and the rod moving past the inlet port had a big detrimental effect.
That prompted the beginnings of the RSA project at Derbi.
Having the carb hanging off the side of the RSW wasnt an issue as far as I know, it was enclosed in an air box, and it has been reported that
due to the required engine position change ( forced by the front pipe exit ) the RSW had better front end feedback than the RSA ,from more forward
weight bias.
Thus though the engine was quicker, alot of riders preferred the RSWs handling.

OK hadn't actually considered the flat vs Narrow side of rod but i was meaning more to narrow the motor to reduce overall width of motor to gain smaller frontal area and possibly larger or less flattened air box design.
Yeah i had picked up on the handling also the exhaust i guess would have been more convoluted design as well rather than a straight rear exit.

ok i must have missed this...

So, Jan Thiel gave his ok. A few pics I found interesting:
"With my friend GJ Rigter at the Aprilia flowbench. The tool in my hand is for flowing the transfers. We flowed them with the piston in 4 different positions."



"The front half of an Aprilia crankcase. The crankshaft could be fixed in various positions by a springloaded ball. We used this for flowbench testing. We could see that the conrod disturbed the flow very much, so the idea of the rear inlet RSA was born!

[Bren_chch]

i've got an 84 dt200lc engine in the shed which i cant find a clutch basket for!

[husaberg]

i've got an 84 dt200lc engine in the shed which i cant find a clutch basket for!

Diferent to the TZR125 and DT125?
There is a thread where a guy is offering to sort out stuff (engines)from Thailand to send over i will Post it here.
http://www.kiwibiker.co.nz/forums/sh...-from-Thailand

Actually now you say the throttle cable on my original MB/H100 was of a DT200R? 0r similar? It had a flat slide with a similar odd long throttle cable fitting to the TZR250 carb i was using. One of the perks at the time of working at a Yam.....er NON Honda dealership guess there were lots of bits to see what fitted what.F-all road bikes though to play with just quads and Ags.
The Non Honda dealer kept a lot of 80-90's stock i can ask him as well, he lives around the corner.

[Yow Ling]

The Non Honda dealer kept a lot of 80-90's stock i can ask him as well, he lives around the corner.

Where you live, everybody lives just round the corner !

[HPbyGD]

@ Glenn

The TZR crank was just big enough to stroke it to 56 mm, The cases had to be trenched to clear the rod and there wasn't a lot of material left. The cranks is smaller than a RZ so that is the reason for the 56 mm stroke. The motor with the DT cylinders held up really well. The welding is to move the studs on the intake side of the cylinders. I built it about 5 years ago and the guy had to bore the cylinders once because we had issues with the Pro X pistons. The pistons broke at the ring land right above the wrist pin. We ended up using Weisco pistons and they held up well. I think that when the guy did track days it would keep up with most of the 600 cc diesel bikes. I never rode the bike but I thought that it must be a lot of fun to pester the 4 strokes and not tell the guys that it was 389 cc's. The only obvious clue is the billet head that I made for it. I have been using Vannik's software and it shows that there should be a good increase in power with the next generation of improvements. We will see. I wish that I had a couple of WR 200 cylinders to use for the build. If anyone has any leads for some cylinders please let me know. I don't know where the motor is that I built with the Athena cylinders as the guy sold it. Last I heard the guy that I built it for ahd got it running well but sold it to buy an other bike. After we had the Athena cylinders replated there weren't any more issues with them. Athena was less than helpful and I didn't fell that there was an advantage worth the trouble and expense of there cylinders. I would like to do something similar to a 3 XT v twin 250, but they are really rare in the US.

Thanks Gary

[husaberg]

@ Glenn

The TZR crank was just big enough to stroke it to 56 mm, The cases had to be trenched to clear the rod and there wasn't a lot of material left. The cranks is smaller than a RZ so that is the reason for the 56 mm stroke. The motor with the DT cylinders held up really well. The welding is to move the studs on the intake side of the cylinders. I built it about 5 years ago and the guy had to bore the cylinders once because we had issues with the Pro X pistons. The pistons broke at the ring land right above the wrist pin. We ended up using Weisco pistons and they held up well. I think that when the guy did track days it would keep up with most of the 600 cc diesel bikes. I never rode the bike but I thought that it must be a lot of fun to pester the 4 strokes and not tell the guys that it was 389 cc's. The only obvious clue is the billet head that I made for it. I have been using Vannik's software and it shows that there should be a good increase in power with the next generation of improvements. We will see. I wish that I had a couple of WR 200 cylinders to use for the build. If anyone has any leads for some cylinders please let me know. I don't know where the motor is that I built with the Athena cylinders as the guy sold it. Last I heard the guy that I built it for ahd got it running well but sold it to buy an other bike. After we had the Athena cylinders replated there weren't any more issues with them. Athena was less than helpful and I didn't fell that there was an advantage worth the trouble and expense of there cylinders. I would like to do something similar to a 3 XT v twin 250, but they are really rare in the US.


Thanks Gary

Plenty of 250's in NZ but mainly RGV and NSR sorry the tzr250 v twin is rearer but not unfindable. The UK may be a cheaper option or Japan as they would be much closer. All The 250 were a popular bike here as we had 250cc learner laws and open second hand imports ex Japan.
the hotspots for the Wr200 seem to be UK USA and AUST. most bits on Ebay seem to be USA no cylinder though i i guess you knew that already. the bits on EBay in the USA for them are quite dear considering.

Where you live, everybody lives just round the corner !

Okay i'll bite Mike
Where i live is has a sub tropical climate is 80% National park and the length of Hamilton to Wellington. Yet where you live is the size of a small lake and the ground stability of a ...... but yeah 3km away is 2 streets and one road and golf course two bridges and one railway line plus the state highway crossing as well. So as i said just around the corner

[2T Institute]

@ Glenn

The TZR crank was just big enough to stroke it to 56 mm, The cases had to be trenched to clear the rod and there wasn't a lot of material left. The cranks is smaller than a RZ so that is the reason for the 56 mm stroke. The motor with the DT cylinders held up really well. The welding is to move the studs on the intake side of the cylinders. I built it about 5 years ago and the guy had to bore the cylinders once because we had issues with the Pro X pistons. The pistons broke at the ring land right above the wrist pin. We ended up using Weisco pistons and they held up well. I think that when the guy did track days it would keep up with most of the 600 cc diesel bikes. I never rode the bike but I thought that it must be a lot of fun to pester the 4 strokes and not tell the guys that it was 389 cc's. The only obvious clue is the billet head that I made for it. I have been using Vannik's software and it shows that there should be a good increase in power with the next generation of improvements. We will see. I wish that I had a couple of WR 200 cylinders to use for the build. If anyone has any leads for some cylinders please let me know. I don't know where the motor is that I built with the Athena cylinders as the guy sold it. Last I heard the guy that I built it for ahd got it running well but sold it to buy an other bike. After we had the Athena cylinders replated there weren't any more issues with them. Athena was less than helpful and I didn't fell that there was an advantage worth the trouble and expense of there cylinders. I would like to do something similar to a 3 XT v twin 250, but they are really rare in the US.

Thanks Gary

Shit easy to put sub exhaust ports in Gary

[Grumph]

@ Glenn

I would like to do something similar to a 3 XT v twin 250, but they are really rare in the US.

Thanks Gary

A few years back when we still had an F2 class here in NZ with an upper limit of 410cc for 2 strokes i was involved on the fringes of a project to enlarge a D model V twin TZ. OE DT200 pistons in iron liners inserted into a couple of damaged TZ barrels. The 2 guys doing it knew what they were doing - one was/is a very good machinist as well as being a top rider. My involvement basically consisted of making encouraging noises....until it was done and they presented me with a pair of hydroformed pipes and asked me to tweak them to fit the bike.
It went quite well but really the only gain was significantly more torque - which on SI circuits is very useful.

Appreciate that, then, replating was not readily available and dynos likewise....

[dinamik2t]

What equipment do you guys use to open up a pair of aux exhaust ports??
I don't have any bench drill or something like that.. I rarely manage to drill both side holes at the same -symmetrical- place/height/angles into the duct.

What I do is dig an approximation of the port into the sleeve and continue about 7-8mm into the cylinder walls, using the right-angle handpiece; I then drill through the duct with a long 6mm drill -eye accurately,electric drill- until I meet the port.
Here's a few shots of results:


It would be interesting to incorporate an angle-adjustable, steady drilling method, but I haven't given any thought on building something like that. It sucks when you know the proper equipment exists and because of cost/availability, you have to think of a home-made system to achieve similar results..

[breezy]

came across this while looking for carb set up info.. its not about carbs but may be of some use to someone...i dont think ive seen it posted on here before, so i apologise in advance if it has...............http://atom007.heimat.eu/tmt/head.html

[HPbyGD]

Hi Guys

I draw the combustion chamber before I machine it. The Cad program that I have will tell me what the volume it is once I make a solid model. One of the things that I don't have is what the volume is of the spark plug. Does any one know what the volume would be of some of the more common spark plugs ? I ma using the NGK BR9ESC plugs in the TZR motor.

I would like to hear about how you guys are cutting aux exhaust ports ?

Thanks Gary

[2T Institute]

What equipment do you guys use to open up a pair of aux exhaust ports??
I don't have any bench drill or something like that.. I rarely manage to drill both side holes at the same -symmetrical- place/height/angles into the duct.

What I do is dig an approximation of the port into the sleeve and continue about 7-8mm into the cylinder walls, using the right-angle handpiece; I then drill through the duct with a long 6mm drill -eye accurately,electric drill- until I meet the port.
Here's a few shots of results:


It would be interesting to incorporate an angle-adjustable, steady drilling method, but I haven't given any thought on building something like that. It sucks when you know the proper equipment exists and because of cost/availability, you have to think of a home-made system to achieve similar results..

As good a method as any .

[wobbly]

Using a 10 plug there is 2.2 cc in the plug hole.
When drawing a chamber in CAD, with a straight line across where the threaded hole would be, you add 0.2 cc to the calculated vol.
A 9 series I would say was closer to 0.3cc.

[Kickaha]

A few years back when we still had an F2 class here in NZ with an upper limit of 410cc for 2 strokes i was involved on the fringes of a project to enlarge a D model V twin TZ. OE DT200 pistons in iron liners inserted into a couple of damaged TZ barrels. The 2 guys doing it knew what they were doing - one was/is a very good machinist as well as being a top rider. My involvement basically consisted of making encouraging noises....until it was done and they presented me with a pair of hydroformed pipes and asked me to tweak them to fit the bike.
It went quite well but really the only gain was significantly more torque - which on SI circuits is very useful.

Appreciate that, then, replating was not readily available and dynos likewise....

Mark and Brian? I've seen a couple of barrels in a guys shed that fit that description